Method for alkoxylation of chlorides and bromides of trivalent phosphorus

ABSTRACT

This invention relates to an improvement in the process of condensing chlorides and bromides of trivalent phosphorus with alkylene oxides to give corresponding Beta -haloalkyl esters of phosphorous acid, useful in the manufacture of fireproofing agents, growth regulators etc. The improvement comprises performing the condensation in the presence of a catalytic quantity of a suitable organic aluminum compound, whereby the reaction proceeds efficiently and substantially without competing side-reactions. In a preferred embodiment of this invention, the organic aluminum compound is used in conjunction with a suitable stabilizing base selected from organic amines and phosphines.

Demarcq 1 1 Aug. 12, 1975 [22 Filed:

[ METHOD FOR ALKOXYLATION OF CHLORIDES AND BROMIDES OF TRIVALENTPHOSPHORUS [75] Inventor:

[73] Assignee: Produits Chimiques Ugine Kuhlmann, Paris, France Jan. 16,1974 [21] Appl. No.: 433,709

Michel Demarcq, Lyon, France [30] Foreign Application Priority Data Feb.21, 1973 France 73.06041 52 US. Cl 260/977; 260/977 51 Int. c1. c07r9/141; C07F 9/142; c071= 9/145;

58 Field of Search 260/977 [56] References Cited UNITED STATES PATENTS2,157,164 5/1939 Daly et a1. 260/977 2,866,809 12/1958 Kolka 260/9773,324,205 6/1967 Carpenter et a1... 260/977 X 3,557,260 1/1971 Gurgiolo260/977 l/l974 De Marcq 260/977 3,804,927 4 1974 Lawson et al.....260/977 3,810,961 5/1974 Pivajver 260/977 FOREIGN PATENTS ORAPPLICATIONS 1,032,240 6/ 1958 Germany 260/977 Primary ExaminerRichardL. Raymond Attorney, Agent, or Firm-Pennie & Edmonds [5 7] ABSTRACT Thisinvention relates to an improvement in the process of condensingchlorides and bromides of trivalent phosphorus with alkylene oxides togive corresponding B-haloalkyl esters of phosphorous acid, useful in themanufacture of fireproofing agents, growth regulators etc. Theimprovement comprises performing the condensation in the presence of acatalytic quantity of a suitable organic aluminum compound, whereby thereaction proceeds efficiently and substantially without competingside-reactions. In a preferred embodiment of this invention, the organicaluminum compound is used in conjunction with a suitable stabilizingbase selected from organic amines and phosphines.

9 Claims, N0 Drawings METHOD FOR ALKOXYLATION OF CHLORIDES AND BROMIDESOF TRIVALENT PHOSPHORUS BACKGROUND OF THE INVENTION It is known that thechlorides and bromides of trivalent phosphorus react with alkyleneoxides to give corresponding B-haloalkyl esters of phosphorus acid whichhave a host of uses, particularly as intermediates in the manufacture offireproofing agents, growth regulators resented by equation (I) whereinX is C1 or Br.

Numerous examples of this type of condensation are cited in Houben-WeylMethoden der Organischen Chemie Vol. XII/l, p.209-2l0, 324 and 327 andVol. XII/2, p. 17-18, 50 and 69-70.

The best known example is the reaction of phosphorus trichloride withethylene oxide, according to equa tion (2) and the instant inventionwill be described chiefly with reference to this particular reaction,without however in any way limiting thereby the applicability of theinvention to the general class of reactions according to equation (I).

In practice, reaction (2) is carried out by simply introducing liquid orgaseous ethylene oxide into the agitated phosphorus trichloride in theabsence of atmospheric moisture and usually at a temperature maintainedwithin the range of about lO-70C, by cooling.

Phosphorus trichloride is readily available and the trichloroethylphosphite made by reaction (2) has a ready market for numerous syntheticpurposes. In particular trichloroethyl phosphite can easily betransesterified by other alcohols or polyols, condensed by the Birumreaction with acetaldehyde and dialkylphosphorochloridites, condensedwith haloalkanes to give various alkanephosphonates (Michaelis-Arbuzovreac- "tion), or isomerised by heating to form bis-(B- chloroethyl)B-chloroethane phosphonate, which itself 'is frequently encumbered byquite long periods of induction and momentary accumulation of largeexcesses of ethylene oxide in the reactor which can lead to suddenreactions approaching explosive violence. To explain these facts, it hasbeen advanced that the presence of small trace of hydrochloric acid isnecessary in order that reaction (2) can take place by the catalyticaction of HG] according toequations (3) and (4):

and other useful products. The general reaction is rep- 10 Inconsequence, it has been P p to add a small quantity of hydrochloricacid or a compound which generates hydrochloric acid such as phosphorusacid or chloroethanol (US. Pat. No. 2,877,260; French Pat. No.1,450,320) or a metallic chloride such as magnesium chloride (JapanesePat. No. 67/19576.) However, hydrochloric acid is objectionable becauseit also leads to side reactions, as discussed further below, and therebylowers the yield of pure trichlorethyl phosphite.

The prior art methods further result in trichloroethyl phosphite of lowpurity. The proportion of undesirable secondary products obtained canreach as high as 15 or even 20%, consisting principally of monooroligophosphonates resulting from the rearrangement of the trichloroethylphosphite, with or without the liberation of dichloroethane and possiblyof secondary phosphites. Such harmful effect on purity is higher whenthe phosphoric trichloride used contains traces of hydrochloric acid orwhen hydrochloric acid or a metallic chloride is added deliberately ascatalyst.

The reactions producing the impurities are not completely understood. Inparticular, the phosphonates would not seem to originate from a simpleMichaelis- Arbuzov transposition or condensation as in reactions (5) and(6) inasmuch as these reactions do not proceed rapidly except attemperatures, such as C, verye much above the usual temperature ofethoxylating phosphorus trichloride.

When commercial grades of phosphorus trichloride are used, these usuallycontain a small proportion, generally about between 0.2 and 0.7 percent,of phosphorus oxychloride, POCl This gives rise to a further difficulty,in that phosphorus oxychloride reacts extremely slowly with ethyleneoxide, even in the presence of hydrochloric acid. Thus the POCl isconverted at best to chloroethyl chlorophosphates which still havesufficient of the original hydrolyzable chloride atoms to impart apotential acidity, i.e. subsequent contact with traces of moistureresults in the liberation of hydrochloric acid. The resultant acidity isharmful to good preservation of the trichloroethyl phosphite,particularly when packaged in contact with metals.

It has been found that the phosphorus oxychloride impurity can bequantitatively ethoxylated in the presence of a conventional Lewis acidsuch as TiCL ZrCl... FeCl AlCl and the like. These catalyze also theethoxylation of phosphorus trichloride, but have the disadvantage ofincreasing side reactions and thus, as in the case of hydrochloric acid,lower the yield of pure trichloroethyl phosphite.

Without intending to be bound by theoretical considerations, a possiblemechanism whereby hydrochloric acid may catalyze the formation of theundesirable secondary products may be represented by equations (7) tol).

' x I Briefly stated, the instant invention comprisesanimpresence of asmall quantity of amine. However, the I conditions for achieving thedesired effect are extremely involved and hard to reproduce. As has beenpointed out by A.N. Pudovik and EM. Faizullin (Zhurnal Obschei Khimii1962, 32, 231-7 and 1964, 34, 882-9) and as the present Applicant hasverified on many. occasions, the addition of amines also inhibitsreaction (2), aswould be expected'if one accepted the mechanism of (3)and (4). Said patent recognizes implicitly the hindering role of amine;although the amine is described as catalyst, it is recommended, to avoidkilling the reaction, that it should be introduced gradually'in solutionin the epoxide. Thus even if such operation can be made to workeffectively, it is encumbered by a number of drawbacks, among whichthere is that of rendering necessary, when one uses ethylene oxide, aspecial agitation equipment under pressure for the solution of theamine. It may also be dangerous because the amines are catalysts ofthepolymerisation of epoxides. t

In short, the'present state of prior artdoes not permit achievingethoxylation of commercial phosphorus trichloride in a completelysatisfactory manner which is reproducible and safe and yields atrichloroethyl phosphite of satisfactory purity, I

' SUMMARY OF THE INVENTION A means hasnow been found whereby chloridesand bromides of trivalent phosphorus can be more efiiciently condensedwith epoxides thanbefore. Exemplarily, a means has been found wherebycommercial phosphorus trichloride can safely and conveniently beethoxyla'ted by ethylene oxide to produce tri(chloroethyl) phosphite ofsatisfactory purity in high yield.

provement in the method of alkoxyla ting chlorides'and bromides oftrivalent phosphorus with an'epoxide. Said improvement comprisesperforming said alkoxylating in the presence ofa 'suitable'catalyticquantity of an organic aluminum compound having the formula:

where Q, Q, and Q' can be the same or different from each other and caneach be C C alkyl, or aryl C C alkoxyl or aryloxyl and can have one ormore hydrogens substituted by halogen or by crosslinking ether oxygen,amine nitrogen 'or alkylene bridges to form ring structures. 7

i In a'preferred embodiment of this invention, the improvement includesusing in conjunction with said organic aluminum compound a suitablestabilizing base selected from the group consisting of organic aminesand organic phosphines. Whereas it has been surprisingly 'found that theorganic aluminum compound of this invention by itself can reduce theextent of side reactions leading to undesirable by-products, theadditional presence of the stabilizing base improves still further theavoidance of competing side reactions.

DETAILED DESCRIPTION The organic aluminum compound of this invention canbe any such compound having the formula AlQ'Q"Q"' where the three groupsQ, Q", and Q' chemically bound to the aluminum atom can be the same ordifferent from each other and can beC C alkyl, or aryl C -C alkoxyl oraryloxyl. Thealkyl and alkoxyl "groups can be saturated or unsaturated,straight-chained, branched or cyclic. The alkyl can exemplarily bemethyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert. butyl,hexyl, 2-ethyl hexyl, n-octyl, ndecyl, propenyl, isopropenyl, n-butenyland the like; the alkoxyl can'be methoxide (methylate), ethoxide(ethylate), -n-propoxide (n-propylate), isopropylate, tert. butylrate,sec. butylate, neopentylate, 2-ethyl hexylate, n-decylate,.-n-octylateand the like. Any of these alkyl aryl, alkoxyl. and aryloxyl groups canhave one or more of its hydrogens substituted by ahalogen. Thus,-without thereby limiting the: invention, there can .exemplarily bementioned 2-chloroethylate, 2-

Thus the organic aluminum compound of this invention canexemplarily betrimethyl, aluminum, triethyl' aluminum, tri(n-propyl) aluminum, diethylpropyl aluminum, ethyl dipropylaluminum, tri(isopropyl alumi- I num,tri(n-butyl) aluminum, tri(isobutyl) aluminum, tri(tert.butyl) aluminum,tri(n-hexyl) aluminum, tricyclohexyl aluminum, tri(2-ethylhexyl)aluminum,tri (noctyl) aluminum, tripropenyl aluminum, tri(isoprope nyl)aluminum, tri (n-butenyl) aluminum, aluminum trimethylate, aluminumtriethylate, aluminum tri(npropylate), aluminum tri(isopropylate),aluminum tri(- sec.butylate), aluminum tri-neopentylate, aluminum monoethylate di-neopentylate, aluminum tri(2- ethylhexylate), aluminumtri(n-octylate), aluminum tri(n-decylate), aluminum triphenate, aluminumtri( 2- chloroethylate), aluminum tri(m-chlorophenate), di ethylaluminum isopropylate, ethyl aluminum di(isopropylate), diethyl aluminumphenate, dialuminum tri(diethylene glycolate). Without limiting theinvention thereby, there can be mentioned as further examples ofaluminum organic compounds having ring structures, aluminumnitrilotriethylate which has one nitrogen atom joining three Q groupsinto two rings and aluminum acetylacetonate and aluminum dimedonatewhich have alkylene bridges.

The amount of organic aluminum compound which can advantageously be usedin carrying out this invention can be between 0.01 and 3 mols per 100mols of total phosphorus in the chloride or bromide to be alkoxylated.The dose of organic aluminum compound can thus range from 0.01 to 3 molpercent of the total phosphorus, the preferred dose ranging from 0.02 to0.2 mole percent.

The stabilizing base of this invention, which can also be termed anadjuvant or secondary stabilizer, can be any suitable amine orphosphine. Tertiary amines and tertiary phosphines are preferred.

Thus the amine can be aliphatic or aromatic, straightchain, branched orcyclic. Without limiting the invention thereto, there can be mentionedexemplarily, trimethylamine, triethylamine, di-isopropylamine,tributylamine, tert.-butylamine, dicyclohexylamine, tricyclohexylamine,ethyl-2-hexylamine, N,N'dimethyl coco-amine, dimethyl benzylamine,N,N-dimethyl aniline, N,N-diethylaniline, diphenylamine, pyridine,quinoline, alpha-picoline, 2-methyl, S-ethyl pyridine, dimethylethanolamine, triethanolamine, diethylethanolamine, dimethylisopropanolamine, and N- methylmorpholine, while among the phosphinesthere can be mentioned exemplarily tributylphosphine,tricyclohexylphosphine, trioctylphosphine, diphenylphosphine,triphenylphosphine, tris-(hydroxymethyl) phosphine, tris-(cyano-2-ethyl) phosphine, tris- (diethylaminoethyl) phosphine,tris-(pdimethylaminophenyl) phosphine and P- phenylphospholane.

The amount of stabilizing base which can advantageously be used incarrying out this invention can correspond to up to 5 mols per 100 molsof total phosphorus in the chloride or bromide to be alkoxylated. Thedose of stabilizing base can thus range from O to 5 mol percent of thetotal phosphorus, the preferred range being between 0 and 0.03 molpercent.

The molar ratio of stabilizing base/organic aluminum compound isadvantageously between 0 to 3.

The respective mechanisms, whereby the organic aluminum compound andstabilizing base of this invention achieve their functions, areincompletely understood. The aluminum compound surprisingly has acatalytic effect on the overall reaction of equation (2) similar to thatof hydrochloric acid but without also causing side-reactions to occursuch as those which occur when hydrochloric acid or conventional Lewisacids are used.

It is particularly surprising that a substantial reduction of by-productformation is obtained even in the ab sence of stabilizing base. AlthoughApplicant does not wish to be bound by theoretical considerations, theadditional reduction in competing by-product reactions effected in thepresence of the stabilizing base is probably attributable to buffering(neutralization) of traces of free hydrochloric acids. Surprisingly thebenefits of this buffering by amine can be gained when the alumi numcompound of this invention is also present without the above describedprior art complications attributed to inhibition of reaction (2).

A possible modification of this invention is to combine the organicaluminum compound together with the stabilizing base in the form of acoordination complex and to introduce all or part of the organicaluminum coumpound and stabilizing base into the reaction medium in thiscoordinated complex form, which can be completely or incompletelysoluble in the reaction medium. This modification is illustrated inExample 9 herein by the use of a l/l molar coordination complex oftri(isobutyl)aluminum with triethylamine.

The halides of trivalent phosphorus to which this invention applies canbe described by the general formula X P:-Y Z where X can be chlorine orbromine, Y and Z can each (independently of each other) be chlorine orbromine or a monovalent radical R-, RO-, RS- or RRN- wherein R isselected from the group of C -C radicals consisting of alkyl, alkenyl,cycloalkyl, cycloalkenyl, aryl, alkylaryl and arylalkyl radicals andtheir derivatives wherein one or more hydrogen atoms are substituted bychlorine, bromine, oxygen, sulfur, nitrogen or phosphorus and wherein Rcan be hydrogen or R and wherein R and R can together form a ring andwherein Y and Z also can together form a ring.

By way of non-restrictive examples of phosphorus halides which can beused according to the invention, there can be mentioned phosphorustrichloride, phosphorus tribromide, ethyl dichlorophosphite,2-chloroethyl dichlorophosphite, bis-(2-chloro-ethyl) chlorophosphite,bis-( 2bromo-ethyl) bromophosphite, 2- chloro l-propyl-dichlorophosphite, 1 ,3-dichloro-2- propyl-dichlorophosphite,2-chlorol 3 ,2- dioxaphospholane-4,9-dichloro-3 ,5 ,8 1 O-tetraoxa-4,9-diphospha-[5,5]-spiro-undecane, phenyl dichlorophosphite, paraphenylenebis-(dichlorophosphite), 2- chloro l ,3 ,2-benzodioxaphospholine,O,S-diethyl chlorothiophosphite, 2-chloro-l ,3,2- dithiaphospholane,diethylamino dichlorophosphine, bis-(dimethylamino) chlorophosphine,2-chloro-3- methyl-'1 ,3,2-oxazaphospholane, ethyldichlorophosphine,diethylchlorophosphine, phenyldichlorophosphine,diphenylchlorophosphine, l-chlorophosphorinane, lO-chloro-S 1O-dihydrophenophosphazine, p-p'-bis-(dichlorophosphino) biphenyl, butylbenzenephosphonochloridite, diethylamino-ethylchlorophosphine.

Among the epoxides to which this invention applies, there can bementioned by way of non-restrictive examples of oxides of ethylene,propylene, 2,3-butylene, cyclohexene, styrene, the monoor dioxides ofvinylcyclohexene, of dicyclopentadiene, of dipentene, theepihalohydrins, the ethers and esters of glycidyl, the epoxidized fattyoils and esters, and the epoxy resins.

. In the simplest mode of putting the process of this invention intoeffect one first of all charges the whole of the phosphorus halide, theorganic aluminum compound, any stabilizing base and any inert diluentand then, when agitating and cooling, one gradually introduces theliquid or gaseous epoxide in a slight excess. When the exotherm (i.e.liberation of heat of reaction) has ceased, one distils off the excessof epoxide in vacuo and if necessary one filters the remaining prod-UCt.

The reaction can take place in an autoclave under pressure or atatmospheric pressure, in a reactor equipped with an efficient refluxcondenser capable of refluxing the whole of the reagent. The temperaturecan be advantageously between 30 and +1 C with a preference for therange from +l0C to +60C.

As optional inert diluent there can be used, for example,l,2-dichloroethane, tetrachloroethylene, methylene chloride, diethylether, isopropyl ether, dioxane, benzene, hexane, cyclohexane.

As has been mentioned above, it is not necessary for the organicaluminum additive or the stabilizing base or any coordination complexformed by them together to be completely soluble in the reaction medium.

In an alternative embodiment of the process according to this invention,it is possible at the beginning of the reaction to charge only a part ofthe phosphorus halide, the organic aluminum compound, any stabilizingbase and any inert diluent, the remaining portions being addedsubsequently during the course of alkoxylation, either separately or asa mixture. Such additions can be gradual and continuous, or they can bein finit increments.

In still another embodiment of the process of this invention, thealkoxylation can take place, continuously or semi-continuously, usingfor example a cooled graphite absorption column. Thus, in the case ofmanufacturing trichloroethyl phosphite, such as column can be fed at thetop with phosphorus trichloride containing the organic aluminum compoundand optionally the stabilizing base either in solution or in a stablesuspension while gaseous ethylene oxide is introduced at the bottom ofthe column. The product recovered from the column by vacuum distillationcan then yield either completely converted trichloroethyl phosphite or apre-condensate to be recycled.

This invention will be further illustrated by description in connectionwith the following examples of the practice of it. In these examples andelsewhere herein, the proportions are expressed as parts by weightexcept where specifically statedto the contrary. Those examplesdesignated as control are not illustrations of the method ofthisinvention but show, on the other hand, disadvantages andunsatisfactory results encountered in using prior art procedures nothaving the benefit ofthe organic aluminum compound of this inventioneither alone or in combination with a stabilizing base.

Those examples which do illustrate the instant invention showsubstantially superior results as compared to the corresponding controlexamples, satisfying more completely the following ideal conditions:

paper within a short time after the last addition of epoxide.

D. Highoverall rate of conversion with the absence of P-l-lal or P(O)Halbonds in the condensate after distilling off the excess epoxide. Thelatter are expressed as"hydrolyzable Cl and determined by hydrolysis inaqueous autone .(ll-l room temperature) and subsequent argintimetry ofthe freed l-lCl.

E. High, almost quantitative yield, by weight, of final vacuum-strippedcondensate, -i.e. close to theoretical. (The undesirable formation ofphosphonates is accompanied by the formation of volatile dichloroet'hanewhich manifests itself in a decreased yield by weight.)

F. Content of saponifiable chlorine (by boiling 5 hours in half normalalcoholic potash) close to theory.'

. NOTE: The production of volatile dichlorethane which accompanies thatof phosphonates leads also to a lowering of the percentage ofsaponifiable Cl in the final stripped condensate. Furthermore, in thephosphonates themselves, the percentage of saponifiable Cl is lower thanthe percentage of total C] contrary to what is observed 'in the case ofpure trichloroethyl phosphite in which the whole of the Cl issaponifiable in accordance with the reactions (1 l) and (12):

With bis-(chloroethyl) chloroethane phosphonate, on the other hand,alkaline saponification only removes little more than 2 out of the 3atoms of chlorine present because of the slowness of the saponificationof the phosphonic monoester (equation 15) and of that of the directnucleophilic displacement of the Cl (equation .16): rapid:

vclcngcm P0 (OC2H4CU2 2. CH2 =CH Po.

00 3,01 +KCl H2O slow:

CH =CH PO (OC H CI) EtO CH =CH PO (OC H Cl) (OCH OEt) Cl A low contentof saponifiable Cl is generally accompanied, and this is normal, by toohigh a content of total phosphorus.

G. High content of tri-co-ordinate phosphorus, that is to say oftertiary phosphites or of secondary phosphonites; these compounds weredetermined in general by iodometry or in some cases by mercurimetry oras specifically indicated by NMR.

H. Low contents of phosphonates (or phosphinates) as determined byinfrared spectrometry or by the NMR and of secondary phosphites (orphosphonites) (determined chemically or by NMR).

EXAMPLE l (control) A 3-necked flask equipped with an agitator and areflux condenser cooled by brine at -C was charged with 1 mol ofcommercial phosphorus trichloride containing 0.55 percent by weight ofphosphorus oxychloride (determined by P NMR), at a temperature of 20C.Then after purging the atmosphere of the flask with dry nitrogen, 140 gof gaseous ethylene oxide (or an excess of 6.2 percent over theoretical)was introduced over a period of approximately 3 hours through a tubedipping into the liquid. Heat of reaction was generated immediately andthe temperature rose in a few minutes to 40-50C; temperature thenmaintained in range of 40-50C. by cooling the flask.

Immediately after the addition of ethylene oxide was completed, thereaction mixture still had a pungent odor and was still acid to pHpaper. The mixture was left standing for 2 hours and was then strippedunder mm of mercury at 50C. The remaining phosphite had the followingproperties:

96.85% of theory Yield by wei ht Refractive index n,,*" Hydrolyzable ClSaponifiable Cl Total Tertiary phosphites Analysis by 31,- NMR 1,255 ppm1 37.2% (theory 39.5) 80%, as P (OC H Cl) EXAMPLE 2 (control)trichloride. Because no heat of reaction was observed sulted in only aninsignificant evolution of heat but after about 10 minutes the reactionstarted up suddenly and the temperature rose rapidly to 70C. In order tocontrol the reaction and terminate it normally as in Example 1, it wasnecessary to use a much greater excess of ethylene oxide (approximately25%). The following properties were found for the trichlorethylphosphite obtained after stripping in vacuo:

yield by weight 98.3% of theory Hydrolyzable C1 50 ppm Saponifiable C137.9%

Total phosphorus l 1.66% (theory: 11.5)

Tertiary phosphites 92%, as P(OC H C1) Secondary phosphites 0.22% asHPO(OC H C1) Phosphonates 7.3% as Cl C H PO (OC H CI) (by infrared)EXAMPLE 4 (control) Example 3 was repeated except that there was addedto the phosphorus trichloride 0.2 percent by weight of chloroethanol ascatalyst and that an 8 percent excess of ethylene oxide was used. Nodelay of exotherm was observed in this case and the reaction could becontin ued throughout under normal conditions. However, the followingunsatisfactory properties were found for the end product:

Yield by weight 96.2% of theory Hydrolyzable C1 990 ppm Saponifiable CI37.3% v

Tertiary phosphites 81.5% as P(OC H Cl) Secondary phosphites 2.15% asHPO(OC H C1) EXAMPLE 5 (control) Example 4 was repeated except that theexcess of ethylene oxide was raised to 20 percent and in addition to thechloroethanol, 0.6 percent by weight of pyridine was added, reckoned onthe phosphorus trichloride.

- Once again, the exotherm of the reaction was irregular.

after the addition of approximately 15 g of ethylene oxide, the mixturewas gently heated. At about 25C a sudden violentreaction took place withvigorous boiling and an uncontrollable evolution of ethylene oxide. Thususe of a base in the absence of the aluminum compound of this inventionis not satisfactory.

EXAMPLE 3 (control) Example 1 was repeated except that carefullypuri- 1fied phosphorus trichloride was used, containing less than 0.1 percentof POCl and practically no HCl. The

EXAMPLE 6 (control) Example 1 was repeated except that 0.21 percent byweight of titanium tetrachloride was added to commercial phosphorustrichloride containing 0.75 percent of POCl The exotherm was vigorousand regular throughout the entire] introduction of the ethylene oxide,using a 7 percent excess during which time the temperature wasmaintained at between 40 and 50C. The analysis of the filtered endproduct gave:

Yield by weight 96.6 percent of theory Hydrolyzable C1 30 ppmSaponifiable CI 37.25%

Tertiary phosphites as P(OC H CI) EXAMPLE 7 Example 6 was repeatedexcept that in place of the TiCl there was used tri-isobutyl aluminum inan amount corresponding to 0.036 percent by weight of PC1 A markedexotherm was observed from the very I 3 .899 I 1 1 beginning of theethylene oxide injection. The excess of ethylene oxide used was 1percent. The slightly turbid end product was stripped in vacuo aspreviously and filtered, yielding a colorless and' limpid phosphite withthe following properties, showing'improved yield using the aluminumcompound even without stabilizing base:

- Yield by weight= 99.2% of theory I-Iydrolyzable Cl 30 ppm SaponifiableCl 38.05%

Tertiary phosphites 91% as P(OC I-I Cl) EXAMPLE 8 Using the procedure ofExample 1, 1 mol of phosphorus trichloride containing 0.3 percent ofPOCl was reacted with ethylene oxide in 1 percent excess in the presenceof 0.18 percent by weight of triisobutyl aluminum and 0.20 percent ofdiethylethanolamine reckoned on the phosphorus trichloride. The reactionmixture, which was very opalescent at the beginning, became practicallyclear at the end of the reaction (excess of ethylene oxide 1%). No delayin exotherm was observed.

The analysis of the stripped and filtered end product gave the followingresults indicating still further improvement in presence of also astabilizing base.

Yield by weight 99.65% of theory I-Iydrolyzable Cl 135 ppm SaponifiableCl 38.4%

Tertiary phosphites 94% as P(OC H Cl) EXAMPLE 9 EXAMPLE 10 Example 9 wasrepeated, except that the reaction temperature was maintained at between2 09and 30C. The results were as follows:

Yield by weight 97.2%

I-Iydrolyzable Cl 50 ppm Saponifiable Cl 38.5%

Tertiary phosphites 94.5% as P(OC I-I.,C1)

EXAMPLES 11 to 17 Example 6 was repeated, replacing the TiCl by aluminumisopropylate either in association or not with a secondary stabilizer.The special operational conditions and the results are set out in thetable below (the percentages shown are percentages by weight).

A series of experiments was thus carried out in each of which one mol ofcommercial phosphorus trichloride as in Example 6 was condensed underconditions 20 recorded in the accompanying table. In each case aluminumisopropylate was used as catalyst, the respective amounts based onphosphorus trichloride, being given in the second column of the table.In Example llpno secondary stabilizer was used. In experiments 12-17,

secondary stabilizers were used as given in the table. In

ments l6 and 17 contained larger amounts of yellow precipitate. I I

In the case of Example-17, the P NMR analysis gave the followingcomposition:

P(OC H Cl);, 97.9% H P O (OC ILCU 0.4% OP(OC,H.,C1);, 1 .6% Phosphonates'not visible (iso-PrO);,Al Secondary stabilizer Excess of Phosphiteobtained (filtered) Tertiary ("/1 of PCl Nature of ethylene Yield byHydrolyz- Saponifphosphites PCl oxide used weight able Cl iable Cl 72 as(7r reckoned (/1 of (ppm) (71) P(OC ,H..Cl);; on theory) theory) 0.08nil 2.7 99.6 25 38.2 '92 0.2 bLN-dimethylaniline 0.2 6.2 99.4 10 38.593.9 0. Tributylamine 0.15 7 99.0 25 38.4 94.5 do. 0.15 9 98.6 250 38.6594.7 diethyl ethanolamine 0.10 l 1.8 98.4 .20 38.45 94.3 0. tributyl- 1v r phosphine 0.32 8.5 99.4 38.85 97.5 0. triphenyl- T 9 phosphine 0.4713 99.8 300 38.95 98.5

num/triethylamine; in amount corresponding to 0.26 EXAMPLE 18 percent byweight of PCI;., dissolved in 3 mls. of petroleum ether; the excess ofethylene oxide'used was 11 percent. No delay was observed in theexotherm. Temperature was maintained at 4050C throughout. The

analysis of stripped and filtered end product gave:

Into an enamelled .lO-Iiter' autoclave provided with blade agitationthere were placed'20-mols of phosphorus trichloride (containing 0.75percent of phosphorus oxychloride) and there was added to'this 0.1percent by weight of aluminum isopropylate and 0.1 percent by weight ofdiethyl ethanolamine. 60.5 mols of liquid ethylene oxide were graduallyintroduced incrementally over 6 hours, cooling so that the temperaturedid not temperature of 55C and was then filtered so as to'elim inate aslight turbidity. There was finally obtained 5,374 g of trichlorethylphosphite, or a yield by weight of 99.7%. The analysis gave thefollowing results:

Hydrolyzable Cl 60 ppm Saponifiable C1 38.2% Tertiary phosphites 95.5%as P(OC H Cl) EXAMPLE 19 One mol of phosphorus chloride was condensedwith an amount of ethylene oxide corresponding to l 18% of thetheoretical quantity in the presence of aluminum nitrilotriethylate inamount corresponding to 0.18% by weight of the PCl No delay in exothermwas observed. The end product contained in suspension a large quantityof insolubles which were separated by filtration. The analysis of thefiltrate gave:

Yield by weight 98.0%

Hydrolyzable Cl 40 ppm Saponifiable C1 38.1%

Tertiary phosphites 92.4% as P(OC l'l.,Cl)

EXAMPLE 20 Example 15 was repeated except that in place of the aluminumisopropylate there was used aluminum tertiary butylate (tert.-BuO) Al inamount 0.13 percent by weight of PCI The excess of ethylene oxide usedwas percent. No delay in exotherm was observed.

The slightly opalescent end product was not filtered.

Yield by weight 98.0%

Hydrolyzable C1 22 ppm Saponifiable C1 38.65%

Tertiary phosphites 94.4% as P(OC H CI) EXAMPLE 21 A similarcondensation of PCl was carried out, using aluminum secondary butylate(sec.-BuO) Al in amount of 0.14 percent by weight of PCl The excess ofethylene oxide used was 15 percent. No delay in exotherm was observed.The end product which was slightly opalescent, was not filtered:

Yield by weight 98.5%

Hydrolyzable C1 18 ppm Saponifiable C1 38.4%

Tertiary phosphites 94.6% P(OC H Cl) EXAMPLE 22 EXAMPLE 23 (control) Ina three-necked flask equipped with mechanical agitation and a refluxcondenser, there was placed at ambient temperature 1 mol of commercialphosphorus trichloride titrating 1.55 percent of POCI 3.1 1 mols(excess= 3.7%) of liquid propylene oxide were introduced dropwise usinga dropping funnel.

The temperature rose rapidly and the flask was cooled so as to maintainit at i 5C.

After all exotherm had ceased the mixture was allowed to stand for 12hours at ambient temperature. The excess of propylene oxide was thenremoved in vacuo (t 50C, p 15 mm Hg). The analysis of the phosphiteobtained gave:

Yield by weight 98.8%

Hydrolyzable C1 1800 ppm Saponifiable C1 33.2% (theory 34.2)

Tertiary phosphites 80.7% as P(OC H Cl) This example is not anillustration of the instant invention but illustrates the propoxylationof PCI;; in the absence of the catalyst and secondary stabilizer of thisinvention.

EXAMPLE 24 Using the procedure of Example 23, but adding to the PCl 0.2percent by weight of aluminum isopropylate and 0.2 percent by weight ofalpha'picoline, and using a 5.4 percent excess of propylene oxide, therewas obtained a product with the following properties:

Yield by weight 99.6%

Hydrolyzable C1 155 ppm Saponifiable C1 33.2%

Tertiary phosphites 91.8% as P(OC l-l Cl) The presence of the catalystand adjuvant of this invention substantially increased the yield.

EXAMPLE 25 (control) Example 23 was repeated, replacing the propyleneoxide by epichlorohydrin. As no exotherm was found in the cold, thephosphorus trichloride was brought to boiling point. Then thetemperature was maintained at between and 100C. Even at thesetemperatures, the exotherm was not immediate after each addition ofepichlorophydrin, whose overall charge had a stoichiometric excess of 10percent. A standing for 3 hours at to C was necessary in order to ensurethat the reaction mixture no longer reddened Prolabo pH paper.Evacuation at 50C under 0.5 mm Hg. succeeded in removing only part ofthe epichlorohydrin.

The residue, a turbid liquid, was filtered and analysed:

Yield by weight 101.5% Hydrolyzable C1 550 ppm Saponifiable C1 49.55%(theory: 51.3) Tertiary phosphites Approx. 89% as P(OC H Cl (bymercurimetry) Free epichlorohydrin approx. 3.5% (by proton NMR)Phosphonates light P 0 band in infrared at 1260 EXAMPLE 26 Example 25was repeated, adding to the PC1 0.21 percent by weight of aluminumisopropylate and 0.19 percent of N-methylmorpholine. This time thereaction started off in the cold and it was possible to carry it outcompletely without exceeding 50C. For a same excess of epichlorohydrinas that in Example 25 a supplementary standing period of one hour at 50Cwas suflicient to cause the disappearance of any acidity which could bedetected with pH paper. After evacuating as in Example 25, to removeexcess of epoxide, a turbid product was obtained which, afterfiltration, gave the following analysis:

Yield by weight 101.7% Hydrolyzable C1 40 ppm Saponifiable Cl 51.3%Tertiary phosphites approx. P( OC l-l Cl (by mercurimetry) Freeepichlorohydrin approx. 0.9% Phosphonates P band still weaker than inExample 25.

EXAMPLE 27 (control) The operation was carried out as in Example 1 butreplacing PCl by phenyl dichlorphosphine. Although no delay in exothermwas observed, the final reaction mixture, despite an excess of 20percent of ethylene oxide, remained acid to pH paper even after standingfor 4 hours at approximately 20C. After removing the excess of ethyleneoxide by evacuation at 50C under 15 mm Hg, one obtained aphenylphosphonite complying with the following characteristics:

Yield by weight 97.4%

Hydrolyzable Cl 1050 ppm Saponifiable Cl 24.4% (theory 26.6)

Secondary phosphonites 60.4% as C l-l EXAMPLE 28 Example 27 wasrepeated, adding to the phenyl dichlorophosphine 0.13 percent by weightof aluminum tertio-butylate and 0.22 percent of triphenylphosphine. Forthe same excess of ethylene oxide as in Example 27, the end reactionmixture no longer showed any acidity which could be detected with pHpaper and the supplementary standing time could be dispensed with. Thephenylphosphonite obtained after vacuum stripping contained insuspension a yellowish insoluble which had to be separated byfiltration.

Yield by weight 99.0%

Hydrolyzable C1 200 ppm Saponifiable C1 25.9%

Secondary phosphonites 90% as C H EXAMPLE 29 (control) The operation wascarried out as in Example-23, replacing PCl by cyclic ethylenechlorophosphite (also known as 2-chloro-1,3,2-dioxaphospholane) and thepropylene oxide by cyclohexene oxide (containing 5% of1-methyl-cyclohexene-oxide). The reaction was immediately exothermic andit was possible to conduct it throughout without exceeding 50C. However,the final reaction mixture (containing a total excess of epoxides of20%) was acid to pH paper. A supplementary heating for 45 minutes at 75Cdid not succeed in causing this acidity to disappear.

Finally the mixture was vacuum stripped at 88C under 0.7 mm Hg so as toyield a somewhat opalescent phosphite giving the following analysis:

Yield by weight 101.0%

Hydrolyzable C1 1340 ppm Saponifiable Cl 16.3% (theory: 15.8 Tertiaryphosphites 89.5% (expressed as phosphite /Y ol CH EXAMPLE 30 Example 29was repeated with the same excess of epoxide but adding to the ethylenechlorophosphite 0.2% by weight of aluminum tertio-butylate and 0.17% oftriphenylphosphine. Again the final reaction mixture was acid to pHpaper, but 15 minutes of heating at 75C was sufficient to cause thisacidity to disappear. The phosphite obtained after vacuum distillationas in Example 29 contained an insoluble which was collected on thesurface after a few hours and which was eliminated by skimming.

Yield by weight 102.4%

Hydrolyzable C1 260 ppm Saponifiable C1 16.1%

Tertiary phosphites 89.2% as phosphite .1

EXAMPLE 3 1 (control) Example 1 was repeated, replacing PCl byphosphorus tribromide (containing 0.15% of POBr and cooling sufficientlyfor the temperature to remain in the vicinity of +20C. The reactionstarted off spontane-' ously. Towards the end an orange precipitate richin phosphorus was deposited. The final mixture, containing an excess of20% of ethylene oxide, was slightly acid to pH paper; it was allowed tostand overnight in a refrigerator but this did not cause this acidity todisappear. After stripping at 20C under 0.6 mm Hg and filtration oneobtained tris(2-bromo-ethyl) phosphite ,EXAMPLE 32 Example 31 wasrepeated, adding to the PCl 0.15 percent of aluminum tertio-butyl-ateand 0.25 percent of t'riphenylphosphine. No delay in. exotherm wasobserved. There was again 'noted the formation of an without delay atambient temperature under 0.6 mm' Hg and was then filtered.

Yield by weight 98.9% Hydrolyzable Br 1,900 ppm Saponifiable Br 58.8%

where X can be chlorine or bromine, Y and Z can each (independently ofeach other) be chlorine or bromine or a monovalent radical R-, RO-, RSor RRN- wherein R is selected from the group of C,C radicals consistingof alkyl, alkenyl, cycloalkyl, cycloalkenyl, aryl, al-

kylaryl and arylalkyl radicals and their derivatives wherein one or morehydrogen atoms are substituted .by chlorine, bromine, oxygen, sulfur,nitrogen or phos phorus and wherein R can be hydrogen or R and wherein Rand R can together form a ring and wherein Y and Z also can togetherform a ring,

the improvement which comprises performing said alkoxylating, in thepresence and absence of a stabilizing base, and in the presence of asuitable catalytic quantity of an organic aluminum compound selectedfrom (1 compounds having the formula Q1 i n where Q, and Q and Q' can bethe same or different from each other and can each be C C alkyl or aryl,

dimedonate.

C,C, alkoxyl or aryloxyl and can each have one hydrogen substituted byhalogen aluminum nitrilotriethylate, (3) aluminum acetylacetonate and(4) aluminum 2. The improvement of claim 1 which includes using inconjunction with said organic aluminum compound a suitable stabilizingbase selected from the group consisting of tertiary amines and organicphosphines.

3. The improvement of claim 1 wherein the aluminum compound is aluminumnitrilotn'ethylate.

4. The improvement of claim 1 wherein the aluminum compound is aluminumacetylacetonate.

5. The improvement of claim 1 wherein the aluminum compound is aluminumdimedonate.

6. In the method of claim 1 wherein phosphorus trichloride isethoxylated by ethylene oxide, the improvement of claim 1 whereinethoxylation is performed in the presence of a tri(C C, alkyl) aluminumor an aluminum tri (C -C alkoxylate).

7. The improvement of claim 6 wherein the ethoxyla tion is performed inthe presence of a tertiary amine or organic phosphine.

8. In the method or reacting phosphorus trichloride having as animpurityphosphorus oxychloride in the amount up to about 5 percent based on theweight of phosphorus trichloride, with ethylene oxide in amount up toabout 3.6 mol per mol of total phosphorus,

the improvement comprising reacting the phosphorus trichloride andethylene oxide, in the presence and absence of a stabilizing base, andin the presence of a tri (Cy-C 0) alkyl aluminum or an aluminum tri(C,C,alkoxylate), in the amount corresponding to from 0.01 to 3 mols per molsof total phosphorus.

9. The improvement of claim 8 wherein in conjunction with said aluminumcompound there is present a stabilizing base selected from the groupconsisting of tertiary amines and organic phosphines, in amountcorresponding to from 0 to 5 mols per 100 mols of total phosphorus.

Page 1 of 2 UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OFCORRECTION PATENTNO. 3, 99,550 DATED August 12, 1975 rNv Emom's) MichelDemarcq It is certified that error appears in the above-identifiedpatent and that said Letters Patent e hereby corrected as shown below:

Column 2, line 18, "chlorethyl" should read chloroethyl.

Column 2, line 46, "verye" should read very.

I Column 4, line 44, "butylrate" should read -butylate.

Column 5, line 58, "0 to 3." should read 0 and 3..

Column 6, line 17, "coumpound" should read-compound-.

Column 7, line 41, "such as column" should read such a column.

Column 7, line 64, "control" shoul d read "control".

Column 8, line 13, (1H room temperature) should read (1H at roomtemperature)-.

Column 8, line 26, "saponifiable Cl" should read "saponifiable Cl"-.

Column 10, line 54, "entirel" should read entire--.

Columns 11 & l2, Ex. No. should be inserted.

ll l2 l3 l4 l5 l6 l7 Page 2 of 2 UNITED STATES PATENT AND TRADEMARKOFFICE EERTIFICATE OF CORRECTION Q PATENT NO. 3 899 550 DATED August 12,1975 N 0 (5) Michel Demarcq It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 18, line 2, "halogen aluminum" should read --halogen (2)aluminum--.

. Signed and Scaled this fourth Day of May 1976 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer (mnmr'ssimwr UfPGhf'HSand Trademarks

1. IN THE METHOD OF ALKYOXYLATING CHLORIDES AND BROMIDES OF TRIVALENTPHOSPHORUS WITH AN EPOXIDE, WHEREIN THE TRIVALENT PHOPHORUS CAN BEDESCRIBED BY THE GENERAL FORMULA
 2. The improvement of claim 1 whichincludes using in conjunction with said organic aluminum compound asuitable stabilizing base selected from the group consisting of tertiaryamines and organic phosphines.
 3. The improvement of claim 1 wherein thealuminum compound is aluminum nitrilotriethylate.
 4. The improvement ofclaim 1 wherein the aluminum compound is aluminum acetylacetonate. 5.The improvement of claim 1 wherein the aluminum compound is aluminumdimedonate.
 6. In the method of claim 1 wherein phosphorus trichlorideis ethoxylated by ethylene oxide, the improvement of claim 1 whereinethoxylation is performed in the presence of a tri(C1-C10 alkyl)aluminum or an aluminum tri (C1-C10 alkoxylate).
 7. The improvement ofclaim 6 wherein the ethoxylation is performed in the presence of atertiary amine or organic phosphine.
 8. In the method or reactingphosphorus trichloride having as an impurity phosphorus oxychloride inthe amount up to about 5 percent based on the weight of phosphorustrichloride, with ethylene oxide in amount up to about 3.6 mol per molof total phosphorus, the improvement comprising reacting the phosphorustrichloride and ethylene oxide, in the presence and absence of astabilizing base, and in the presence of a tri (C1-C10) alkyl aluminumor an aluminum tri(C1-C10 alkoxylate), in the amount corresponding tofrom 0.01 to 3 mols per 100 mols of total phosphorus.
 9. The improvementof claim 8 wherein in conjunction with said aluminum compound there ispresent a stabilizing base selected from the group consisting oftertiary amines and organic phosphines, in amount corresponDing to from0 to 5 mols per 100 mols of total phosphorus.